Lustre 1.6 Operations Manual

CHAPTER 33
System Limits
This chapter describes various limits on the size of files and filesystems. These limits
are imposed by either the Lustre architecture or the Linux VFS and VM subsystems.
In a few cases, a limit is defined within the code and could be changed by recompiling
Lustre. In those cases, the selected limit is supported by Lustre testing and
may change in future releases. This chapter includes the following sections:
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Maximum Stripe Count
Maximum Stripe Size
Minimum Stripe Size
Maximum Number of OSTs and MDTs
Maximum Number of Clients
Maximum Size of a Filesystem
Maximum File Size
Maximum Number of Files or Subdirectories in a Single Directory
MDS Space Consumption
Maximum Length of a Filename and Pathname
Maximum Number of Open Files for Lustre Filesystems
OSS RAM Size for a Single OST
33.1 Maximum Stripe Count
The maximum number of stripe count is 160. This limit is hard-coded, but is near the
upper limit imposed by the underlying ext3 filesystem. It may be increased in future
releases. Under normal circumstances, the stripe count is not affected by ACLs.
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